1. Field of the Invention
The present invention relates to an electrical connector having a male and female fitting pair, and more particularly to an electrical connector in which the fitting force for connecting male and female connectors to each other is enhanced by a cam force exerted by an appended lever.
2. Discussion of Related Art
FIG. 11 shows an example of an electrical connector of this kind, in a state where male and female connectors 1 and 2 have not yet been coupled to each other. The one or male connector 1 is in a state where electrical wires 3 are respectively connected to plural terminals, so as to be prepared for fitting with the other or female connector 2. The female connector 2 includes a housing section 2a which is formed integrally with an upper cover 4a of an electrical connection box 4. Referring also to FIG. 2, the connection box 4 includes male terminal portions 4e which are terminal portions of bus bars 4d projecting into the housing section 2a. When the corresponding terminals are to be connected to each other, the male connector 1 is pressed into the female connector 2 so as to be fitted thereinto.
Recently, in an electronic apparatus or an electrical facility, the number of terminals of an electrical connector tends to be relatively large as circuit wiring is formed in a higher density and in a more complex manner. Consequently, in order to surely connect terminals of male and female connectors to each other with a single operation, a large fitting force is required.
To comply with this requirement, an electrical connector having a structure which is provided with a cam lever 5 as shown in FIG. 11 is known. In this case, the lever 5 is coupled with the male connector 1 in a previous production step so as to be assembled therewith, so that it is prepared to be fitted with the female connector 2 in the next production step.
In the lever 5, rotation holes 5i are formed at appropriate positions in the longitudinal direction of the lever body 5a constituting a frame of the lever 5. Support shaft pins 5b extending from side walls of the male connector 1 are respectively inserted into the rotation holes 5i, so that the lever 5 is rotatable about the support shaft pins 5b. The front end portion of the lever body 5a serves as a force application point portion 5c. When the worker applies a pressing force indicated by the arrow P in FIG. 11 to the force application point portion, the lever body 5a rotates about the support shaft pins 5b in a clockwise direction in the figure. Thus, the lever body 5a functions to connect the male and female connectors to each other by a cam action. The fitting and locking functions of the lever 5 are configured in the following manner.
As a fitting mechanism, a lock piece 5e in the form of a cantilever is disposed below the force application point portion 5c of the lever body 5a so as to be located between a pair of right and left slits 5d. An engaging portion 5g projects from the lock piece 5e. The engaging portion 5g is received in an engaging recess (not shown) formed in the inner face of a front side wall 2a of the female connector 2, and the lever body 5a is then undercut-fitted with a single operation and a clicking sensation is experienced due to the elastic deformation of the lock piece 5e.
As a locking mechanism, action point portions 5h project from the rear end portion of the lever body 5a in contrast to the force application point portion 5c in the front end portion. The action point portions 5h are movably and engagingly inserted by a lever rotation operation, into vertical slits 1a in the form of long grooves which are formed in the rear end portion of the male connector 1, respectively. Vertical slits 2b are formed, in a side wall of the rear portion of the female connector 2 at locations respectively corresponding to the vertical slits 1a.
When pressing the male connector 1 into the female connector 2, the body 5a of the lever 5 is operated to rotate in a clockwise direction in the figure. Therefore, the action point portions 5h in the rear end portion of the lever body 5a are engagingly inserted into the slits 2b of the female connector 2. Since the action point portions 5h are engaged in both the slits 1a and 2b, the action point portions 5h push against the rear end portion of the female connector 2, so as to pressingly lock the male connector 1.
FIG. 2 shows an example of the internal structure of the electrical connection box 4. In this example, the housing section 2a of the female connector 2 is formed integrally with the upper cover 4a of the electrical connection box 4. When the male connector 1 is pressingly fitted into the female connector 2 by operating the lever 5, fitting connection between the connector terminals causes the terminals of the electrical wires 3 to be electrically connected to the bus bars 4d on a circuit board 4c laminated between the upper cover 4a and a lower cover 4b.
In contrast, when the electrical connector must be detached from the connection box and the male connector 1 is to be detached from the female connector 2 on the side of the electrical connection box 4, the lever 5 is operated so as to rotate in a counterclockwise direction about the support shaft pins 5b serving as the lever fulcrum. As a result, the locking state due to the lever 5 is cancelled, so that the male connector 1 can be easily detached from the female connector 2.
The electrical connector provided with the lever shown in FIG. 11 has the following problem which remains to be solved. In order to connect the male connector 1 to the female connector 2 on the side of the electrical connection box 4, the male connector 1 and the lever 5 are preassembled in a previous production step as a provisional connector assembly in a semimanufactured state. A large number of such provisional connector assemblies in the form of semimanufactured articles are transported over a long distance, or conveyed in a production line to the next production step of assembling each provisional assembly with the female connector 2.
During such transportation, as shown in FIG. 12, one or more of the electrical wires 3 of one provisional connector assembly may be snagged in a gap C which is formed between the front end portion of the male connector 1 and the free end or force application point portion 5c of the lever 5 associated with another connector assembly. Further, occasionally, the lever 5 of another provisional connector assembly may become snagged in the gap C. When the electrical wire 3 or the lever 5 become snagged, there arises the possibility that the lock piece 5e may be damaged.
It is an object of the invention to provide an electrical connector in which the fitting force for connecting male and female connectors to each other is enhanced by using a cam force exerted by a lever, and, when transported under a provisionally assembled state, a lever or an electrical wire of another connector is prevented from being snagged, thereby preventing the connectors from-being damaged by interference between members.